The study of MRI sequences is not limited to the four previously presented types. Examples of other commonly used sequence types include the Diffusion-Weighted Images (DWI), for the study of the tissue microanatomy via water diffusion, Diffusion Tensor Images (DTI), a variant of DWI that takes into account the tissue's spatial volume, Perfusion-weighted images, for the adequate study of the veins, arteries, and vessels, and Proton Density-weighted (PD) images, for analysis of the water content in tissues [1]}, [2]}, [3]}, [4]}.
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